/**
 * Blend two textures
 */

const BlendShader = {

  uniforms: {

    'tDiffuse1': {value: null},
    'tDiffuse2': {value: null},
    'mixRatio': {value: 0.5},
    'opacity': {value: 1.0}

  },

  vertexShader: /* glsl */`

		varying vec2 vUv;

		void main() {

			vUv = uv;
			gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );

		}`,

  fragmentShader: /* glsl */`

		uniform float opacity;
		uniform float mixRatio;

		uniform sampler2D tDiffuse1;
		uniform sampler2D tDiffuse2;

		varying vec2 vUv;

		void main() {

			vec4 texel1 = texture2D( tDiffuse1, vUv );
			vec4 texel2 = texture2D( tDiffuse2, vUv );
			gl_FragColor = opacity * mix( texel1, texel2, mixRatio );

		}`

};

export {BlendShader};
